Along with the increased use of computers at home and in the workplace, there has been an increase in the number of computer operators who suffer from repetitive stress injuries (RSI) such as carpal tunnel syndrome, wrist and shoulder tendinitis, tennis elbow, neck problems and thoracic outlet syndrome. While considerable efforts have been directed toward providing mechanisms for reducing RSI (e.g., wrist rests, foot stools, mobile arm supports and adjustable chairs), most of those efforts have failed to address the prior computer keyboard as a source of the problem.
Prior computer keyboards commonly include: one flat, generally rectangular, rigid "slab" bearing one hundred or more keys (e.g., standard letter keys in a "QWERTY" configuration or other arrangement, number keys, punctuation keys and function keys) disposed on a top side of that computer keyboard; and a bottom side which serves the limited function of supporting the computer keyboard on a working surface (e.g., a tabletop). Prior computer keyboards are commonly supported on top of the working surface and cannot effectively be positioned away from or operated away from that working surface (i.e., they are "married" to the working surface). Thus, a computer keyboard operator has a limited number of keyboard positions available to adjust such prior keyboards for comfort.
Because many keys are needed to operate a computer (i.e., more than just standard letter keys), prior computer keyboards are necessarily relatively large and, therefore, are clumsy. A computer keyboard operator cannot readily vary the position of such large, slab computer keyboards.
Some prior computer keyboards include two keyboard halves (a split keyboard), which can be varied in position with respect to each other, and keyboard keys which are disposed on the top sides of those keyboard halves. Such prior keyboard halves include bottom sides which are supported on a working surface or a fixed base or which are integral with a computer. Generally, a computer keyboard operator cannot position such keyboard halves far away from the working surface, fixed base or computer. While this prior split keyboard enables a computer keyboard operator to position the keyboard in a greater number of positions than are available with a one-piece, slab keyboard, because of the proximity of the split keyboard to the working surface, fixed base or computer, the number of positions available to the computer keyboard operator is still limited. Additionally, access to the bottom sides of such prior split keyboards is limited or virtually impossible.
Given the general inconvenience in repositioning prior computer keyboards and the limited number of positions for using prior computer keyboards, computer keyboard operators commonly operate such computer keyboards without regularly changing either the keyboard position or their body position or posture. Long-term use of these prior keyboards without periodic changes in keyboard position or body position causes static loading from the elbows to the spine of the computer keyboard operator. Such static posturing can be awkward and uncomfortable and puts the computer keyboard operator at risk for developing RSI. One of the key factors in good ergonomic design is to enable a computer keyboard operator to assume a variety of body positions or postures. It is, therefore, desirable to have a computer keyboard which can be easily positioned in numerous positions and which, in turn, enables a computer keyboard operator to readily assume a variety of body positions while operating the computer keyboard (e.g., upright sitting, sitting cross-legged, reclined sitting, kneel/sitting, standing upright or walking).
Miniaturization of computer hardware also is an important factor in the development of computers and computer keyboards. Some smaller-sized prior computer keyboards include letter keyboard keys (switches) which have multiple functions. However, such multi-function keys are complex to use. Other smaller-sized prior computer keyboards include significantly smaller-than-standard letter keyboard keys. However, such smaller-than-standard letter keys are tiresome to use. It is, therefore desirable to have a computer keyboard which is smaller-sized but includes standard-sized, single-function letter keys.